U.S. Pat. No. 5,162,430, issued Nov. 10, 1992, to Rhee et al. discusses collagen-synthetic polymer conjugates prepared by covalently binding collagen to synthetic hydrophilic polymers such as various derivatives of polyethylene glycol. U.S. Pat. No. 5,324,775, issued Jun. 28, 1994, to Rhee et al. discusses various insert, naturally occurring, biocompatible polymers (such as polysaccharides) covalently bound to synthetic, non-immunogenic, hydrophilic polyethylene glycol polymers. U.S. Pat. No. 5,328,955, issued Jul. 12, 1994, to Rhee et al. discusses various activated forms of polyethylene glycol and various linkages which can be used to produce collagen-synthetic polymer conjugates having a range of physical and chemical properties.
Ser. No. 08/403,358, filed Mar. 14, 1995, discusses a crosslinked biomaterial composition that is prepared using a hydrophobic crosslinking agent, or a mixture of hydrophilic and hydrophobic crosslinking agents. Hydrophobic crosslinking agents can include any hydrophobic polymer that contains, or can be chemically derivatized to contain, two or more succinimidyl groups.
U.S. Pat. No. 5,580,923, issued Dec. 3, 1996, to Yeung et al. discusses a composition useful in the prevention of surgical adhesions comprising a substrate material and an anti-adhesion binding agent, where the substrate material preferably comprises collagen and the binding agent preferably comprises at least one tissue-reactive functional group and at least one substrate-reactive functional group.
U.S. Pat. No. 5,614,587, issued Mar. 25, 1997, to Rhee et al. discusses bioadhesive compositions comprising collagen crosslinked using a multifunctionally activated synthetic hydrophilic polymer, as well as methods of using such compositions to effect adhesion between a first surface and a second surface, wherein at least one of the first and second surfaces can be a native tissue surface.
Japanese patent publication No. 07090241 discusses a composition used for temporary adhesion of a lens material to a support, to mount the material on a machining device, comprising a mixture of polyethylene glycol, having an average molecular weight in the range of 1000-5000, and poly-N-vinylpyrrolidone, having an average molecular weight in the range of 30,000-200,000.
West and Hubbell, Biomaterials (1995) 16:1153-1156, discuss the prevention of post-operative adhesions using a photopolymerized polyethylene glycol-co-lactic acid diacrylate hydrogel and a physically crosslinked polyethylene glycol-co-polypropylene glycol hydrogel, Poloxamer 407®.
U.S. Pat. Nos. 5,672,336 and 5,196,185 describe a wound dressing comprising a micro-particulate fibrillar collagen having a particle size of 0.5-2.0 μm. This composition generally comprises an aqueous phase and may not form a hydrogel as described in the present invention. U.S. Pat. No. 5,698,213 describes a cross-linked aliphatic poly-ester hydrogel useful as an absorbable surgical device and drug delivery vehicle. U.S. Pat. No. 5,674,275 describes an acrylate or methacrylate based hydrogel adhesive. U.S. Pat. No. 5,306,501 describes a polyoxyalkylene based thermoreversible hydrogel useful as a drug delivery vehicle.
U.S. Pat. Nos. 4,925,677 and 5,041,292 describe a hydrogel comprising a protein component cross-linked with a polysaccharide or mucopolysaccharide and useful as a drug delivery vehicle.
Biodegradable injectable drug delivery polymers are described in U.S. Pat. No. 5,384,333 and by Jeong et al. (1997) “Nature,” 388:860-862. Biodegradable hydrogels for controlled released drug delivery are described in U.S. Pat. No. 4,925,677. Resorbable collagen-based drug delivery systems are described in U.S. Pat. Nos. 4,347,234 and 4,291,013. Aminopolysaccharide-based biocompatible films for drug delivery are described in U.S. Pat. Nos. 5,300,494 and 4,946,870. Water soluble carriers for the delivery of taxol are described in U.S. Pat. No. 5,648,506.
Polymers have been used as carriers of therapeutic agents to effect a localized and sustained release (Langer, et al., Rev. Macro. Chem. Phys., C23 (1), 61, 1983; Controlled Drug Delivery, Vol. I and II, Bruck, S. D., (ed.), CRC Press, Boca Raton, Fla., 1983; Leong et al., Adv. Drug Delivery Review, 1:199, 1987). These therapeutic agent delivery systems simulate infusion and offer the potential of enhanced therapeutic efficacy and reduced systemic toxicity.
Other classes of synthetic polymers which have been proposed for controlled release drug delivery include polyesters (Pitt, et al., in Controlled Release of Bioactive Materials, R. Baker, Ed., Academic Press, New York, 1980); polyamides (Sidman, et al., Journal of Membrane Science, 7:227, 1979); polyurethanes (Maser, et al., Journal of Polymer Science, Polymer Symposium, 66:259, 1979); polyorthoesters (Heller, et al., Polymer Engineering Scient, 21:727, 1981); and polyanhydrides (Leong, et al., Biomaterials, 7:364, 1986).
Collagen-containing compositions which have been mechanically disrupted to alter their physical properties are described in U.S. Pat. Nos. 5,428,024; 5,352,715; and 5,204,382. These patents generally relate to fibrillar and insoluble collagens. An injectable collagen composition is described in U.S. Pat. No. 4,803,075. An injectable bone/cartilage composition is described in U.S. Pat. No. 5,516,532. A collagen-based delivery matrix comprising dry particles in the size range from 5 μm to 850 μm which may be suspended in water and which has a particular surface charge density is described in WO 96/39159. A collagen preparation having a particle size from 1 μm to 50 μm useful as an aerosol spray to form a wound dressing is described in U.S. Pat. No. 5,196,185. Other patents describing collagen compositions include U.S. Pat. Nos. 5,672,336 and 5,356,614. A polymeric, non-erodible hydrogel that may be cross-linked and injected via a syringe is described in WO 96/06883.
The following pending applications, assigned to the assignee of the present application, contain related subject matter: U.S. Ser. No. 08/903,674, filed on Jul. 31, 1997; U.S. Ser. No. 60/050,437, filed on Jun. 18, 1997; U.S. Ser. No. 08/704,852, filed on Aug. 27, 1996; U.S. Ser. No. 08/673,710, filed Jun. 19, 1996; U.S. Ser. No. 60/011,898, filed Feb. 20, 1996; U.S. Ser. No. 60/006,321, filed on Nov. 7, 1996; U.S. Ser. No. 60/006,322, filed on Nov. 7, 1996; U.S. Ser. No. 60/006,324, filed on Nov. 7, 1996; and U.S. Ser. No. 08/481,712, filed on Jun. 7, 1995. The full disclosures of each of these applications is incorporated herein by reference. Each publication cited above and herein is incorporated herein by reference in its entirety. There are a variety of materials suitable for use as bioadhesives, for tissue augmentation, for the prevention of surgical adhesions, for coating surfaces of synthetic implants, as drug delivery matrices, for ophthalmic applications, and the like. Yet in many cases the setting time for these materials can be less than optimal, whereas for surgical and other medical applications, a rapidly acting material is often preferred. In other cases, currently available materials may exhibit swelling properties that are undesirable for certain surgical applications. Thus, what is needed is a rapidly acting material, for use as, for example, a tissue sealant for hemostatic and/or wound sealing applications. It would also be desirable to provide materials that exhibit minimal swelling properties.